Letters From Our Readers
To: Editor, The Angle Orthodontist.
Re: A comparative study of the effect of the intrusion arch and straight wire mechanics on incisor root resorption: A randomized, controlled trial. Marcio R de Almeida, Aline SB Marcal, Thais MF Fernandes, Juliana B Vasconcelos; Renato R de Almeida; Ravindra Nanda. The Angle Orthodontist . 2018; 88: 20-26.
Recently, we read the manuscript authored by de Almeida et al.1, who evaluated the magnitude of root resorption by means of Cone-Beam Computed Tomography (CBCT) in patients treated with intrusion arch or continuous archwire mechanic. Although this is a relevant clinical subject, we have very concerns about the acquisition of CBCT exams before and after the patient's treatment, with no apparent justification for ionizing radiation exposure to such a dose other than for the purpose of the study's publication.
According to the ALADA (as low as diagnostically acceptable)2 and the guidelines that support the use of CBCT in Orthodontics, this examination is not indicated for routine diagnosis, it should not be used as the first imaging method to evaluate root resorption, as in the specific case of the research and, mainly, it should not be used exclusively for follow-up without clinical suspicion or justification based on individual patients' evaluation.3–5 Other reasons for concern are the low age range of the patients included in the sample that are more susceptible to the stochastic effects of ionizing radiation, as well as the size of the FOV used since it is not necessary to irradiate the patient's entire head when only a specific region was analyzed.5
Finally, we cannot understand how an ethical committee has approved this project. Considering the respect and appreciation we have for The Angle Orthodontist journal, we hope this letter can make researchers consider this aspect before carrying out similar study in the future.